1. Field of the Invention
The present invention pertains to a three phase fluid flow measuring system including apparatus particularly useful for measuring the gas content and the water content in a gas-water-oil mixture and wherein the compressibility of a fluid sample is measured to determine the gas content and the water cut.
2. Background
The above-reference patent application discloses a system for measuring multiphase fluid flow, particularly mixtures of gas-water-hydrocarbon liquids. The system described in the reference application includes a sampling container which is closable to trap a predetermined quantity of liquid and into which a piston is movable to effect a decrease in the volume of the container chamber while raising the pressure of the liquid therein. This process may be used to measure the pressure/volume change and determine the residual gas content in the liquid as well as, with known liquid components, the fraction of one or more liquid compositions in the liquid. The use of a piston slidable in a cylinder to effect the volume change of the chamber presents certain maintenance and operational hazards and opportunities for error in the measurement process due to fluid leakage around the piston and trapping of bubbles of gas from previous samples of fluid being measured. The present invention overcomes these dificiencies as will be appreciated by those skilled in the art upon reading the following.